Cooling methods and systems, utilized, for example, in distribution cabinets with electrical equipment, emitting a significant dissipated heat energy, providing a generated heat dissipation by virtue of both natural and forced ventilations, are currently in use.
The natural ventilation involves a presence of a large number of ventilation openings and a direct contact with an outside ambient, which does not allow to use such an equipment in areas with high humidity of environment.
The forced ventilation allows to mechanize the cooling of the electrical equipment in sealed cabinets, simultaneously providing a necessary moisture protection. The most common ventilation methods in use include air cooling systems, enclosing heat exchangers, containing a cooling liquid or other refrigerant agents. Such cooling methods require an arrangement of fluid supply and discharge systems, as well as an installation of additional tanks, which leads to complexity of a design, increases its dimensions and affects a prime cost of such equipment.
A known cooling system embodiment constitutes a forced air ventilation excluding using of additional cooling agents.
Mechanical Patent RU2239267 dated 27 Oct. 2004 Int. Cl. H05K 7/20 “Cabinet for Electrical Motor Control Station” sets out a heat removal system, according to which an electronic device comprises an air channel of a rectangular section, having one side wall, coincidently constituting a back wall of an enclosure, while its opposite wall contains a radiator (cooler) surface, comprising gills and electrical equipment mounting spots arranged therein. The air channel is performed between the side walls of the enclosure. An opening, executed on the enclosure back wall in opposite to the radiator surface center, contains an integrated ventilation unit cell. A cell input and air channel outlets, designed as windows on the side walls of the cabinet, are covered with a protective grid.
Disadvantages of this technical solution may include a joint ventilation of all compartments of the device, which can lead to an inefficient use of a cooling devices resource due to a fact that the equipment of a different power and with different degrees of heating is installed inside of the cabinet. In this way, it requires a significant energy consumption to provide a sufficiently cooled air, that is not necessary for all installed equipment.
Also Patent for Utility Model RU158897 of Russian Federation Int. Cl. H05K 7/20 “Composition of Cooling System of Frequency Transformer Inverter Cabinet” sets out a forced air cooling system of a cabinet, containing power and low-current electronic devices, and including guide air channels and at least one blowing fan, and involving at least two independent cooling circuits, available as following: the first circuit is being used for cooling a power part and the second circuit is used for cooling low-current electronic devices. The cabinet with power and low-current electronic devices is divided into isolated sections for an air flows separation, while the power electrical equipment is divided into separate power units, installed onto a wall, separating cells. The first circuit contains the guide air channels, configured to form a pressurized air supply directly to radiators of the power electronic devices of power units, while the blowing fans of the cooling circuits are installed separately and have a different power. The supply of the cooling air in the first cooling circuit is conducted separately for each vertical row of the units along the common guide air channel, equipped with outlet openings, located against each cooler (radiator) of the power unit.
Disadvantages of the technical solution, described in the patent, may include an air supply, executed from a bottom part of the cabinet, which requires an installation of air filters for each of the blowing fans. Also the arrangement of the air channel within the first circuit with outputs for each cooled device can reduce an efficiency of the cooling system due to separating the supplied air flow.
Mechanical Patent No. U.S. Pat. No. 9,545,037 (B2) dated 10 Jan. 2017 Int. Cl. H05K7/20 “System and Method for Electric Drives Cooling” sets out a method of a forced air cooling of an electronic device, according to which an enclosure is made with at least one sealed compartment, protected from an outside ambient contact. This enclosure comprises both power and low-current electronic components, as well as at least one heat exchanger, connected to the sealed compartment. Upper and lower compartments are executed sealed. The upper and lower compartments contain sets of electrical elements. An air channel adjacent to the upper and lower sealed compartments forms a common wall with the aforementioned compartments. In accordance with the described method, the cooling system includes an upper heat exchanger, arranged in the air channel and mounted onto the common wall, providing a possibility of air passing from the upper sealed compartment, as well as a lower heat exchanger unit, arranged in the air channel and mounted onto the common wall, providing a possibility of air passing from the lower sealed compartment. Each of the heat exchangers constitutes an air-to-air cross-type heat exchanger, having a plurality of passageways, formed between rows of plates, central portions of which are substantially planar and parallel.
Disadvantages of the described technical solution may include an arrangement of the power electrical equipment, such as reactors, in a separate sealed compartment, which requires an installation of additional recirculating fans, which adds a complexity to the device design. Also the disadvantages may include installing a main blowing fan outside of the station, which can lead to its rapid wear due to an impact of sand and dust, as well as a separation of the flow into two parts, which requires an increase of the blowing fan power.
The claimed technical solution aims solving a technical problem, constituting a creation of a forced air cooling system of a simplified design and providing effective cooling of both power and low-current electronic components by means of a single directed air flow, as well as a method of an embodiment of the said forced air cooling system.